| 저자(한글) |
LIAO, Weijiao,JIANG, Jiehua,CHEN, Tao,SU, Xiuxin,PAN, Sizheng,XU, Yunjian,YI, Jianyun,WEI, Xiaoping,LI, Yiquan |
| 초록 |
OBJECTIVE To investigate the distribution insertion sequence ISEcp1B in CTX-M-producing Gram-negative bacilli and analyze its polymorphism.METHODS Using Kirby-Bauer susceptibility method to analyze the drug resistance of the strains;to amplify the blaCTX-M-like gene,whole length of blaCTX-M-like gene and the insert sequence ISEcp1B by multiple PCR,the PCR products were sequenced subsequently.RESULTS The genotypes of β-lactamases were CTX-M-G1(41.26%)and ISEcp1B(16.08%),respectively;ISEcp1B was found in 9 isolates of Escherichia coli(ECO)(20.93%),6 isolates of Klebsiella pneumoniae(KPN)(11.32%),5 isolates of Pseudomonas aeruginosa(PAE)(13.89%),2 isolates of Enterobacter cloacae(ECL)(25.00%),and 1 isolate of Citrobacter freundii(CFR)(25.00%);the ISEcp1B positive strains had higher level of resistance to cephalosporin than negative ones;in 8 cases,ISEcp1B was located in the upstream of 5' end of the blaCTX-M-like gene,ISEcp1B might have mobilized the blaCTX-M-like gene through a transposition mechanism and provided 35 and 10 promoter sequences that might drive the expression of blaCTX-M-like gene at a high level;the distance between the two promoters and ATG of the blaCTX-M-like gene was different.CONCLUSIONS Insertion sequence ISEcp1B causes more dangers of horizontal transmission of blaCTX-M-like gene in Gram-negative bacilli,expresses the multidrug resistance phenotypes and has higher level of resistantce. |
